Before you build, be sure to research energy efficient home building information. Energy efficiency is one of the most important aspects of building in the 21st century. There are new building materials and methods that home builders and home buyers alike must stay abreast of. We offer a lot of this sort of information on our site, and in addition you may want to research Energy Star and LEED to get the latest information on their standards and policies.
It is important to determine your goals of energy efficiency before you build. It is very difficult to significantly improve the energy efficiency of an existing structure. It can be done but it is much more difficult to upgrade a home or to reach the maximum levels of efficiency with an existing home, than it is to build it that way from the beginning. Energy efficiency goals vary from one person to another, and may be combined with other ecological values as well as the bottom line of the electric bill.
The R-value of your wall is the total R-value of every single layer of your wall, including air space. For example, a wall from the inside out: A 5/8” panel gypsum wall board has an R-value of 0.62 a half inch panel of fiberboard sheathing offers an R-value of 1.32. One half to four inches of airspace without insulation has an R-value of 1 Vinyl siding with the traditional ½ inch insulation offers an R-value of 1.8
• This means that without insulation between the studs a standard wall has an R-value of 4.74. People who have these sorts of walls pay $300 to $500 in heating and cooling bills every month for less than 2000 square feet of space.
• By adding 3 ½ inches of fiberglass inside the studs the R-value is increased by 12 for a total of almost 17. People who have this sort of insulation pay around $200 per month.
• By adding 3 ½ inches of polystyrene sprayed in you can raise that R value by 19, for a total value of about 24. This is approximately the minimum standard of energy star ratings.
• By adding a 3 ½ inch polyurethane panel between your two by four studs with an R-value of 27, you can reach an R-value of nearly 32.
• However if you start with six inch stud walls you can pack them with a 6 inch poly urethane panel for an R value of up to 65 in some cases.
Anyone who has ever owned an older or historic home knows there are drafts and chilly spots, and that truly no amount of money can heat the home evenly or even adequately in a home with no insulation. Almost anything built today exceeds that standard. It is possible to increase the energy efficiency of an older house, but it is almost impossible to make it truly energy efficient, without ripping out either the interior or exterior wall. Likewise if you build your home to minimum standards and codes you will not ever be able to heat your home adequately, for an affordable price. Today even fiberglass batting is practically obsolete for new homes, but this method of insulation does represent the minimum standards. R factors between 10 and 15 are passé, but some are still built.
For real energy efficiency an R factor of 20 is a good minimum number to consider for walls, but more is of course better. The ceiling and attic require R-38 to be energy star approved. If you can get your walls ceiling and floor more airtight it will make your home easier to heat and cool.
Installing a system of solar panels could offset your electric bill entirely if your home is efficient enough. It is even possible to get a check from your electric company or operate completely independent of them, but this is only economically feasible with maximum energy efficiency.
By creating an energy efficient home, you save on your electric and heating bills for years to come. The upfront costs of energy efficiency are more than paid for in savings over the next eight years or less. Our site is full of energy efficient home building information. Be sure to read all our related articles and download our 98 page free book on home planning to learn more.